| 摘要 |
PROBLEM TO BE SOLVED: To provide an interferometer which easily measures the shape of an aspherical surface having a long radius of curvature. SOLUTION: The interferometer for measuring the shape of the aspherical surface of an object under inspection is equipped with: an interference optical system which divides a light beam from a light source into a light beam under inspection and a reference light beam and allows the light beam under inspection reflected by the aspherical surface of the object under inspection and the reference light beam to interfere with each other; and a photoelectric conversion element for detecting interference fringes caused by the interference of the light beam under inspection and the reference light beam. The interference optical system has: a first optical element for passing and reflecting the light under inspection; a second optical element for reflecting the light under inspection; and a moving means for moving the second optical element. The light beam under inspection is allowed to pass through the first optical element, to be reflected by the second optical element, to be reflected by the first optical element, and to enter the aspherical surface of the object under inspection. COPYRIGHT: (C)2011,JPO&INPIT |
